[Xenomai-help] Xenomai 2.5.1: trace_mark usable on 2.6.30.1 without LTT patch?

[Joerg Albert <jal2@domain.hid>]

Hi,

I run Xenomai 2.5.1 on top of ipipe-2.6.30-powerpc-2.7-01 from
http://git.denx.de/ipipe-2.6.git with Adeos updated from 2.7-01 to 2.7-06.
Platform is a MPC8533.

In order to track down a problem I'd like to use trace_mark() (with my own probe
function), but I'm a bit confused by the code in
include/asm-generic/xenomai/wrappers.h:

#ifdef CONFIG_LTT

#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,24)
#define trace_mark(channel, ev, fmt, args...)	\
	MARK(channel##_##ev, fmt , ##args)
#else /* >= 2.6.24 */
#include <linux/marker.h>
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,27)
#undef trace_mark
#define trace_mark(channel, ev, fmt, args...)	\
	__trace_mark(0, channel##_##ev, NULL, fmt, ## args)
#endif /* < 2.6.27 */
#endif /* >= 2.6.24 */

#else /* !CONFIG_LTT */
#undef trace_mark
#define trace_mark(channel, ev, fmt, args...)	do { } while (0)
#endif /* !CONFIG_LTT */


My kernel doesn't provide CONFIG_LTT and its trace_mark() implementation in
include/linux/marker.h is:
#define trace_mark(name, format, args...)

Does this imply that I have trace_mark inside the Xenomai code only after
applying some additional LTT patch to the kernel?